Method and equipment for the elimination of mine blockades

ABSTRACT

A method for eliminating mine blockades or similar obstacles comprises arranging a blasting charge in the form of an explosive gas or gas mixture or a liquid and/or solid component-gas mixture, such as a foam, over the area to be cleared; and igniting the charge to cause a detonation over the area to effect a detonation of the mines to render them harmless. The explosive is applied to the area by means of an elastic grid formed of a plurality of interconnected hose elements which are gastight and pressuretight and which may be unwound such as by inflation so as to extend outwardly across the mined area. The hose elements of the grid form a receptacle for the blasting gases or the explosive gas liquid or gas solid mixtures such as a foaming material forming the explosive. Alternatively the explosive may be applied to the minefield by means of a rocket or other vehicle containing the explosive foam or its ingredients through a discharge nozzle for ejecting and spreading the explosive over the blockaded area. The recoil from the ejected explosive is utilized to propel the rocket forward and or upward. The explosive may also be ejected through a nozzle gun connected to a container on a land vehicle such as a tank.

United States Patent Messerschmitt-Bolkow Gesellschaft mit beschrankter Haftung 1 Feb. 1, 1972 [54] METHOD AND EQUIPMENT FOR THE 3,112,669 12/1963 Damblanc ..102/49.3 X

ELIMINATION OF MINE BLOCKADES Primary Examiner-Verlin R. Pendegrass [72] Inventor: Frank Rudolf Thomanek, Sandizell, ,41m --M Glew and Toren Germany 73 1 Assignee: Messerschmitt-Bolkow Gesellschait Mit [57] ABSTRACT neschlankler "omlllg A method for eliminating mine blockades or similar obstacles [22] Filed. July 28, 969 comprises arranging a blasting charge in the form of an explosive gas or gas mixture 01' a liquid and/or solid component-gas l2] 1 Appl. No.: 845,148 mixture, such as a foam, over the area to be cleared; and igniting the charge to cause a detonation over the area to effect a detonation of the mines to render them harmless. The ex lo- [30] Fore'gn Apphcamm Pnomy Dam sive is applied to the area by means of an elastic grid formefl of Aug. 1, 1968 Germany ..P 17 03 933.7 a plurality Ofimcrconnectcd hose elements which are Gaslight and pressuretight and which may be unwound such as by infla- [52] us. (:1 ..102/22, 89/1 M tion 50 as to extend outwardly across the mined area- The hose 5] m C| i I I n 3/00 elements of the grid form a receptacle for the blasting gases or [58 1 Field of Search ..102/22, 23; 89/1 M the W gas liquid 01 gas Solid mixtures Such as a fwming material forming the explosive. Alternatively the explosive 56] References Cited may be applied to the minefield by means of a rocket or other vehicle containing the explosive foam or its ingredients UNITED STATES PATENTS through a discharge nozzle for ejecting and spreading the explosive over the blockaded area. The recoil from the ejected 2,455,354 12/1948 BISCh ..l02/22 explosive is utilized to propel the rocket forward and or 219251038 2/1960 walker [02/23 ward. The explosive may also be ejected through a nozzle gun 219671099 1961 Pool 102/23 X connected to a container on a land vehicle such as a tank. 2,975,045 3/1961 Perry et al.. 102/23 X 2,993,648 7/1961 Blackwell ..l02/49.7 X ll Claims, 6 Drawing Figures PATENTEDFEB H972 3.638.569 V SHEET 1 or 2 INVENTUR Franz Rudolf Thomanek B hwwfiw ATTORNEYS PATENTEU FEB I H72 SHEU 2 BF 2 Fig. 5

IHVEFJCF' Franz Rudolf Thomunek BY AT TOR NEYS METHOD AND EQUIPMENT FOR THE ELIMINATION OF MINE BLOCKADES SUMMARY OF THE INVENTION This invention relates in general to a method and equipment for the elimination of mine blockades or similar obstacles, and in particular to a new and useful method for applying an explosive charge over the mined area which is adapted to be detonated in order to detonate the minesand render them harmless.

It is known to destroy mined areas by clearing the explosive charges by hand or by triggering the mines individually by means of rolls or clappers or by the complete removal of the mines by means of drags. It has also been proposed to establish opening wedges or lanes through the mine-infested area by means of an explosive covering the entire area in order to destroy the mines in this manner or at least to cause the pres sure-sensitive fuses of the mines to respond to thus make it possible to cross the blockade without the risk of an after detonation of the explosive bodies. In general this operation is carried out by the use of a flexible blasting charge laid over the mine area in various ways, such as by means of rockets. A fuse cord or several fuse cords tied together like a rope ladder have been used for detonation. In some cases another method is employed in which a plastic'explosive such as one pressed out of a nozzle is laid over the mine blockade in the form of a ribbon. Although such known devices for laying and clearing a blasting charge require complicated preparations and much technical expenditure, they do not function reliably and unobjectably. In addition the transportation of the explosives to the site of their use represents a very real danger for the operating personnel and the transporting vehicle.

In accordance with the present invention there is provided an improved method for overcoming minefield obstacles and for providing a simple means for the transportation of the materials required for laying a clearing-type explosive charge through the minefield without danger to the operating personnel and the transportation vehicles and by greatly simplifying the laying of such explosives. In accordance with the invention a blasting charge is laid across the minefield as an explosive gas or a gas mixture or as a mixture of a gas and a liquid or even of two solid components such as in the form of explosive foams.

The application of homogeneous gases capable of detonation is basically possible in theory. In spite of this, considering the complicated and dangerous handling of homogeneous gases, mixtures of preferably two gas components or suspensions will generally be used in practice as smoke or mist in a gas. In such a mixture, the gas may also be ordinary air.

The advantages achieved by the invention are obvious. Gases may be stored and transported without danger in bottles, perhaps under high pressure or in liquefied state. Mixing the components to form a gas or a mixture which is capable of detonation need take place only immediately prior to the blasting so that all danger to the operating personnel and the transportation vehicle is obviated. In order to save weight and transportation volume, air may be used as one of the gases which may be processed just prior to the blasting operation into a brisant explosive gas by means of a blower with acetylene, for example. Transporting an oxygen component to the site in bottles or in similar containers is thus not required and thus the transportation volume will also be saved.

The gaseous explosive may be composed in a stoichiometric ratio. The explosive gas mixture may also contain a fuel excess which will react with the oxygen of the air suddenly after a first explosion, that is, after the initial detonation there is an after explosion of the residues which are still unreacted with the oxygen of the air. In accordance with another aspect of the invention an explosive substance in the form of gases, liquids or solids or mixtures thereof, in the form of a fog or in the form of a foam may be distributed over the mined area for the purpose of producing an explosion. The composition may include a gas mixture which reacts in a first explosion, and a LII liquid or solid particle mixture which reacts with oxygen of the air in a second explosion. Preferably, due to the first reaction, a reactable mist may be so mixed with the surrounding air that the second reaction will immediately take place following the first in the form of a dust explosion. For example, such an explosion gas may consist of hydrogen and oxygen. It is also possible to use acetylene or carbon disulfide with oxygen or both fuels with air. The invention, however, in the present case is not considered to be limited in respect to the use of the specific substances mentioned, but rather covers generally all explosive gas mixtures or homogeneous gases.

Arranging the explosive gas, the explosive foam or gas mixture over the mine blockaded area to be broken up can be done in the simplest manner in the free air, for example, by flowing out the substance while flying over the blockade with a device such as a remote-controlled rocket which is formed as a carrier. .The fueldroppingdown forms with the. oxygen of W the air an explosive mixture, which, being ignited immediately after being spread, will exert a detonating shock upon the ground and hence upon the mines or their triggering devices. Such an operating mode or arrangement requires small fuel quantities only sufficient to lay a train of fire with energyladen shock waves over the mine blockade. in so doing it is disadvantageous if the materials form droplets when they are blown out or solids which drop in mist form to the ground too quickly. However, if gases are used, they are diffused into the air, and the faster that this is done the more air movement will prevail. In the event of a wind, the concentration quickly drops to values which would no longer permit a detonation. The air space capable of explosion could be moved locally due to an undesired air motion which means that it could be displaced from the minefield and blown away. However, these difficulties are avoided in accordance with the invention by employing a hoselike gas and pressuretight, flexible, elongated container grid which is laid over the blockade area to be eliminated and when so positioned the content thereof is ignited. The grid container serves to receive the explosive gases or the explosive gas and liquid, or gas and solid mixtures. In the unfilled condition, the container is advantageously wound into a coil which is deposited at the edge of the blockade to be eliminated and is permitted to unwind automatically as it is blown up by the explosive gas or by the explosive gas mixture or foam and thus it will lay itself across the blockade.

In a preferred form of grid for this purpose the grid is formed by inflatable hose elements a plurality of which extend parallelly in a longitudinal direction and they are spaced apart and held in the longitudinal orientation by cross hose elements. The resultant structure is a grid or mat form which may be folded and coiled up but which will uncoil and unfold outwardly when blown up. Such mats may be produced at very little cost from plastic materials or from suitable elastic or other rubber materials in suitable sizes and shapes. They may be relatively thin-walled and yet relatively tear resistant so that they can be laid into open terrain without being damaged. Because compressed gases will propagate the explosion faster than uncompressed gases and at speeds approaching that of a solid explosive it is advantageous if the containers are pres suretight, or at least to some extent. It is necessary to determine the amount of gas required and to compare the weight of such gases with those of the gelatinous or solid explosives which have been used heretofore in order to achieve a proper dimensioning of the cross-sectional area of the blasting hoses for mats, and in so doing it can readily appreciate the advantage achieved by the use of such materials over the usual solid explosions.

In accordance with another feature of the invention a rocket powered container containing the explosive mixture or explosive foam flies over the blockade and ejects and spreads the explosive foam as it proceeds. The recoil from the ejected foam may be utilized to propel the rocket of the device either forwardly or upwardly. The aircraft may be in a form of a rocket having discharges or nozzles which are oriented to direct the material downwardly over the blockaded area, or

the material may be carried on a land vehicle and spread over the minefield by spraying it outwardly under a high propelling force.

Accordingly it is an object of the invention to provide a method for eliminating mine blockades or similar obstacles which comprises directing an explosive blasting charge over the blockaded area in the form of an explosive gas, or a gas mixture, or a mixture of a gas and liquid, or of a solid and liquid or gas in the form for example, of a foam, and thereafter igniting the explosive charge to detonate the mines of the blockaded area.

A further object of the invention is to provide an improved device for positioning an explosive over a mined area which comprises an inflatable and windable grid having a plurality of passages in which an explosive is positioned which is adapted to he placed over the blockaded area to be destroyed for exampie by inflation and unwinding of the grid outwardly onto the area.

A further object of the invention is to provide a device for applying an explosive for detonating mines in a minefield which comprises either a rocket or a land vehicle having means for directing the explosive material outwardly in the form of a spray or mist.

A further object of the invention is to provide a device for exploding mines in a blockaded area which is simple in design, rugged in construction and economical to manufacture.

The various features of novelty which characterize the in vention are pointed out with particularity in the claims annexed to and forming a part of this specification. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference should be had to the accompanying drawings and descriptive matter in which there are illustrated preferred embodiments of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings:

FIG. 1 is a top perspective view of a hose mat for applying an explosive charge over a minefield as constructed in accordance with the invention;

FIG. 2 is a view similar to FIG. I of another embodiment of mat;

FIG. 3 is a view similar to FIG. 2 of still another embodiment of mat;

FIG. 4 is a schematic side elevational view of a vehicle in a mat laying position;

FIG. 5 is a schematic side elevational view of a rocket employed for laying an explosive charge in a minefield;

FIG. 6 is a schematic side elevational view of a tank vehicle employed for laying an explosive in a minefield.

GENERAL DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawings in particular the invention embodied therein comprises an explosive carrying mat or grid generally designated 50 which includes four longitudinally extending hose portions 1, 2, 3 and 4, which are combined at their filling end by intermediate hose pieces 5, 6, 7 and 8, to form a common mouthpiece or filling part 9. Attached to the conical mouthpiece is a filling hose l0 and a lead in for a fuse cord 11. A suitable fuse (not shown) is disposed inside the mouthpiece for igniting the explosive which is adapted to be contained in the mat 50 after the mat is laid over a mined area in an extended position as indicated in FIG. 1. The mat 50 also includes cross members or connecting hoses 27, 28, 29 and 39, 3] and 32, etc., extending between the longitudinal members l, 2, 3 and 4 along the entire length of the mat. The mat 50 thus provides explosive-filled parts which cover a plurality of small rectangular fields which when the mat is extended will be distributed over the complete minefield area which is to be cleared of mines. The spacing of the individual rectangular areas is such that the blasting effect at any point of the field is sufficient when the hose is detonated to cause the fuses of the mine to respond even if they are hidden in the screened fields or are at locations alongside the hoses.

In the embodiment indicated in FIG. 2 there is provided a mat or grid generally designated 52, which includes longitudinally extending side hoses l3 and 14, which are combined into a mouthpiece l2 and which are connected by a plurality of crossmembers, in this example two crossmembers l5 and 16. The structure of the mat 52 is similar to that of a ladder and in its rolled up condition the hose will require very little space and may be easily stored. Several such blasting mats 52 may be provided and arranged in side-by-side arrangement if wider lanes are to be blasted through the minefield.

In the embodiment indicated in FIG. 3 a blasting mat generally designated 54 comprises three longitudinal hoses l8, l9 and 20 which are interconnected by transverse hoses 21, 22, 23, 24 etc. The hoses 21, 22, 23, 24 etc., are arranged in herringbone fashion and extend obliquely. The longitudinal elements are combined to a mouthpiece 25 which is connected to a filler hose 26 andit is equipped with a lead in for an electrical fuse cord 33. The mats 50, 52 and 54 may be transported in a folded condition before they are inflated. In the construction indicated in FIG. 3 the outer hoses are folded to the middle before the empty hose mat is rolled up so that the longitudinal hoses l8, l9 and 20 lie literally next to each other as shown in the rear portion of FIG. 3. In the folling of the device up into coil the three longitudinal elements 18, 19 and 20 may be accommodated in a space which is not much greater than that of the construction of mat 52 indicated in FIG. 2.

As indicated in FIG. 4 a hose mat generally designated 56 is shown being laid by a vehicle such as a tank 58. It should be noted that the tank 58 or other armored vehicle need only be driven up to the beginning 62 of the minefield and the coiled hose mat 56 is then deposited in front of the tank and permitted to unwind by being inflated. The mat 56 is filled through an inflation line 60 to cause the mat to unwind as il lustrated. The hose may be filled with a gaseous or foamy explosive and as the filling progresses the mat will gradually extend into the minefield.

The detonation is started by means of a detonator with retardation so that it will spread quickly through the longitudinal and transverse hoses and cover the mined widty. The mines deposited below the mat are made harmless even if the blasting hoses are detonated at a distance above the ground.

In the arrangement indicated in FIG. 5 a rocket 35 is equipped with control surfaces or wings 42 and includes nozzles 36 for spraying an explosive foam 37. The rocket 35 may be guided across the minefield by remote control and the explosive foam 37 is ejected during flight and will drop to the ground and cover the overflown area of a mined terrain in the manner of a carpet 38. The recoil of the explosive escaping through the nozzle 36 can be utilized to propel the rocket 35 forwardly and/or upwardly as desired. The explosive foam carpet 38 which is deposited will be detonated for example by a detonation line such as a hose 62 filled with a cletonating explosive 63, which for example may have a weighted end 64 which is shot across the minefield or even laid by the rocket 35 as it progresses.

In the embodiment indicated in FIG. 6 an armored land vehicle or caterpillar tractor vehicle 39 includes a large container 40 which contain ingredients required to generate a foam in the form of an explosive mixture of a solid, liquid or gas. The foam is deposited over the mined area to be cleared by directing it outwardly under pressure through a nozzle gun 41 so that it is deposited as a blanket 37 which settles on the ground and is subsequently detonated by a device similar to the arrangement indicated in FIG. 5.

By way of example the invention may be carried out by the use of an oxyhydrogen gas. The invention is not restricted to such an explosive mixture but may be employed for all explosive gases, explosive foams and gas mixtures. When an oxyhydrogen gas is employed it may for example have a density of 1.3 kgJm". This means compared to the density of traditional blasting charges in a solid state which extends over a range of 1,500 to l,750 kg./m for an identical explosive volume, less than one fifteen-hundredths weight units of the explosive gas are required in comparison with the conventional explosives. in other words instead of a 1.5 square centimeter fuse cord cross section, a hose of roughly 250 mm. diameter could be filled with an explosive gas in order to blast a wide lane through a minefield. For armored vehicles to pass through, for example, it is necessary to dispose a plurality of mats 52 next to each other with some space therebetween. An arrangement of such mats 52 which extend in longitudinal and transverse directions with a 100 to 300 mm. diameter and attached at a screen spacing of from 100 to 500 mm., will be adequate for the purpose of clearing the minefield. The detonation initiated at one point will quickly spread through the longitudinal and transverse hoses of the mats 50, 52 and 54 and over the entire blockade width through which the mats extend. As tests are proving clearing by explosion is possible when the blasting hoses or mats are detonated even at a spaced location above the ground. The pressure exerted on the ground will suffice to bring about the detonation of the mines.

What is claimed is:

1. A device for laying an explosive blanket over a minefield or similar obstacle comprising a grid having a plurality of longitudinally extending hose elements interconnected by a plurality of transversely extending hose elements, said hose elements being formed together in pressuretight and gastight manner and being in communication with a common filling opening, filling means for filling said hose with an explosive mixture, and ignition means extending through said grid for igniting the explosive mixture therein.

2. A device according to claim 1, wherein said grid is made up of bendable hose elements, said grid being windable into a coil, said filling means including a blower for blowing the explosive charge into said grid in a manner to cause the grid to uncoil as it is being filled.

3. A device according to claim 1, wherein said grid comprises at least four laterally spaced longitudinal hose portions a plurality of transverse hose portions interconnecting said longitudinal hose portions.

4. A device according to claim 3, wherein said transverse hose portions extend at right angles to said longitudinal hose portions.

5. A device according to claim 3, wherein said transverse hose portions extend obliquely to said longitudinal portions.

6. A device according to claim 5, wherein said mat may be folded up by moving said longitudinal portions into side-byside juxtaposition and folding said oblique transverse portions, said mat being uncoilable when blown up and being also unfoldable laterally to each side during its uncoiling.

7. A device for laying an explosive charge in a minefield comprising an aircraft, means for propelling an aircraft over the minefield, container means on said aircraft for storing an explosive mixture in the form of a gas, liquid and gas liquid and solid mixture, and nozzle means connected to said container means for blowing the mixture out in the form of a foam or veillike blanket which is laid over the minefield by said aircraft.

8. A device for applying an explosive blanket over a minefield comprising a movable vehicle a container carried on a vehicle, and nozzle means connected to said container for directing an explosive mixture outwardly as a spray which will settle as a blanket over the minefield.

9. A method for eliminating mine blockades or similar obstacles using a blasting charge comprising a gas mixture containing a fuel excess, comprising laying a blanket in the form of a grid or solid area of the blasting charge in the form of a mat, foam or mist over the area, igniting the blasting charge to cause a first detonation and explosion and after the first explosion igniting the excess fuel by reacting it with oxygen of the air whereby to cause triggering of the mines to render them harmless.

10. A method according to claim 9, wherein said explosive charge comprises a multiple component mixture of gases and liquid or solid substances distributed in the mixture in the form of a fog or mist or a foam, and wherein a part of the gas mixture is reacted in a first explosion and the liquid or solid particles are mixed with the oxygen of the air and reacted in a second explosion.

11. A method for laying an explosive blanket over a minefield or similar obstacle course using a grid having a plurality of longitudinally and transversely extending interconnected hose elements formed together in a pressuretight and gastight manner, comprising filling the hose elements with an explosive mixture to cause it to spread out over a minefield, and igniting the explosive mixture to cause an explosion in the minefield. 

1. A device for laying an explosive blanket over a minefield or similar obstacle comprising a grid having a plurality of longitudinally extending hose elements interconnected by a plurality of transversely extending hose elements, said hose elements being formed together in pressuretight and gastight manner and being in communication with a common filling opening, filling means for filling said hose with an explosive mixture, and ignition means extending through said grid for igniting the explosive mixture therein.
 2. A device according to claim 1, wherein said grid is made up of bendable hose elements, said grid being windable into a coil, said filling means including a blower for blowing the explosive charge into said grid in a manner to cause the grid to uncoil as it is being filled.
 3. A device according to claim 1, wherein said grid comprises at least four laterally spaced longitudinal hose portions a plurality of transverse hose portions interconnecting said longitudinal hose portions.
 4. A device according to claim 3, wherein said transverse hose portions extend at right angles to said longitudinal hose portions.
 5. A device according to claim 3, wherein said transverse hose portions extend obliquely to said longitudinal portions.
 6. A device according to claim 5, wherein said mat may be folded up by moving said longitudinal portions into side-by-side juxtaposition and folding said oblique transverse portions, said mat being uncoilable when blown up and being also unfoldable laterally to each side during its uncoiling.
 7. A device for laying an explosive charge in a minefield comprising an aircraft, means for propelling an aircraft over the minefield, container means on said aircraft for storing an explosive mixture in the form of a gas, liquid and gas liquid and solid mixture, and nozzle means connected to said container means for blowing the mixture out in the form of a foam or veillike blanket which is laid over the minefield by said aircraft.
 8. A device for applying an explosive blanket over a minefield comprising a movable vehicle a container carried on a vehicle, and nozzle means connected to said container for directing an explosive mixture outwardly as a spray which will settle as a blanket over the minefield.
 9. A method for eliminating mine blockades or similar obstacles using a blasting charge comprising a gas mixture containing a fuel excess, comprising laying a blanket in the form of a grid or solid area of the blasting charge in the form of a mat, foam or mist over the area, igniting the blasting charge to cause a first detonation and explosion and after the first explosion igniting the excess fuel by reacting it with oxygen of the air whereby to cause triggering of the mines to render them harmless.
 10. A method according to claim 9, wherein said explosive charge comprises a multiple component mixture of gases and liquid or solid substances distributed in the mixture in the form of a fog or mist or a foam, and wherein a part of the gas mixture is reacted in a first explosion and the liquid or solid particles are mixed with the oxygen of the air and reacted in a second explosion.
 11. A method for laying an explosive blanket over a minefield or similar obstacle course using a grid having a plurality of longitudinally and transversely extending interconnected hose elements formed together in a pressuretight and gastight manner, comprising filling the hose elements with an explosive mixture to cause it to spread out over a minefield, and igniting the explosive mixture to cause an explosion in the minefield. 